Percival s



P. S. TICE;

CARBURTER GOVERNING DvlcE.

APPUCATION FILED MAY 10| |917-- RENEWED MAY 1.1919

l 32 1 ,2 6 1 Patented Nov. 11, 1919.'

UmTE'n STATES PATEN onnicn.

PERCIVAL S. TICE, F WASHINGTON, DISTRICT OF COLUMBIA.

CARBURETER-GOVERNING DEVICE.

Specification of Letters Patent.

Application led Hay 1.0, 1917, Serial No. 167,787. Renewed May 1, 1919.Serial No. 294,097.

To all whom t may concern.'

Be it known that I, PnRcrvAL S. TICE, a

Vcitizen of the United States, residing at 715 ings, forming a partthereof.

The purpose of this invention is to provide improved means for governingthe air supply to a carbureter for an internal combustion engine. Itconsists in the elements and features of construction shown anddescribed, as indicated in the claims.

In the drawings, the sole figure is a partly sectional view of a sideelevation of a carbureter equipped with this invention, section beingmade axially with respect to the air inlet and the valve therein.

The drawing shows in conventional or customary form the loat chamber, A,of a carbureter, from which the liquid fuel is discharged through anozzle, B, into a Venturi tube or constricted throat-way, C, of thesuction passage, D, leading to the engine intake (not shown). Thesuction passage has the air inlet encompassed by a valve seat, 2, facinginwardly, seating the valve, 3. This valve is a hollow or chamberedbody, most conveniently cylindrical in outline, having its chamber, 3a,opening inwardly toward the suction passage; and it is mounted forguidance in its movement toward and from its seat on a stem, 4, whichprojects inwardly from a bridge, 5, extended across the air inlet. Rigidwith the inner end of this stem, 4, there is a head, 6, which beingrigid with the stem is thereby rigid with the valve seat, 'and which ispositioned in the open inner end of the chambered valve, and is adaptedto operate piston-wise therein in the opening and closing movement ofthe valve. A spring, 7 reacts between the head and the body of the valvefor normally seating the valve by the action of the spring, andresisting its opening by the suction. The stem, 4, is axial hollow, andlthe duct, 4a, therein is continuous from a duct, 5, in the bridge, 5,said bridge, as illustrated, having an axially positioned boss, 5", inwhich alsothe duct extends, opening radially therefrom for the purposeof controlling the exterior end by a valve member, 8, mounted upon theprotruding boss, 5", of said bridge, having an aperture, 9a, forregistering with the radially opening end of the duct, and adapted to berotated on said projection for varying the opening, or closing itentirely. A spring, l1, reacting between a washer, 12, on the end of astem, 13, which projects from said axial boss, 5b, of the bridge, and asecond washer, 14, which bears against the outer end of said valvemember, operates to keep the valve snug on its seat, which is tapered tofurther assist this result. The duct, 4a, in the stem, 4, opens into thepiston chamber of the valve, as seen at 4". The head or piston, 6, isconstructed for limited leakage, past it from the piston chamber, 3, ofthe valve, 3, into the suction passage, D, which.

leakage may be effected either by having said piston head slightly loosein the piston chamber, or byv providing it with a small aperture, 15, asshown, or both. Since, as will be understood, the valve is definitelyand accurately carried on the stem, 4, and does notV rely upon thepiston for its guidance, it isr practicable to make this piston asuiciently loose t to insure limited leakage, and the advantage ofobtaining the leakage in this manner is that at the same time thefricthe drawing, the valve 3, operating asthe throttle valve of thecarbureter, remains upon its -seat when the engine is. started,

notwithstanding thepartial vacuum created by the engine suction in thepassage, D, be-

cause the admission of atmospheric pressure through the ducts, 5a and 4Linto the chamber 3a, of the valve, equalizes theppressu'rey 4uponopposite sides of the.. valve. Underv this condition of operation,which: corresponds to very slow rotation ofthe engine crank, as intheidling of the engine, airl flowing from the .exterior through thecontinuous ducts 5a, 4a, and aperture, 4", into,` the chamber, 3a, ofthevalve, 3, passes also to av small extent past the piston, virtue of theleakage provided eitheraround the working edgeof the piston `orthroughvthe aperture, 15. vThis' leakage being veryE much less than the capacityof the passages by which the atmospheric pressure is admitted to thechamber, 3a, does not eiiect any material reduction of the pressure inthe chamber, 3, below atmospheric, and the valve is held seated underthe action of the spring. The valve, 8, being adjusted to restrict theair inlet through the ducts, 5a .and 4a, to the chamber, 3a, thepressure in that chamber will be reduced below atmospheric, and such airinlet being reducd suiiciently by the adjustment of the valve, 8, 'thepressure in the chamber, 3, will become lowered by the leakage past thepiston, 6, until the excess of atmospheric pressure on the outer face ofthe vvalve over the reduced pressure within will be suiicient toovercome the resistance of the spring, 7 so that the valve will beopened by the atmospheric pressure to greater or less extent, dependentupon the degree of suction operating in the suction passage, D, and theextent to which the air access through the ducts, 5a et,

is restricted by the adjustment of the valve,

8; and when the chamber, 3a, is completely Shut on" from communicationwith the atmosphere bythe complete closing of the valve, 8, the pressurewithin the chamber, 3, will be reduced to that existing in the suctionpassage, D. The spring, 7, is designed to be of'such stiffness thatvunder these conditions the valve, 3, will vbe wide open. It will beunderstood that one Jfunction of the spring, 7, is to maintain withinthe suction passage, D, such degree of pressure lower than atmosphericas to be adequate to supe f ply the carbureter with the liquid fuel bytheA suction of the engine. When the valve 3, isopen to any extent, thesuction in the passage,y D, is reduced,-tliat is, the pressure isVraised,by reason of the entrance of the air past `thevalve, and theleakage past thepiston is reduced. At any given degree of opening of thevalve, 8, equilibrium between thefinternal and external pressure on thevalve, 3,`-including in the .internal pressure of the resistance of thespring,7,-will be attained at a certain degreeof suction in the passage,D; and the degree of suction being dependent upon the speed of theengine, it follows that the degree of opening of the valve, .8, willrsubstantially determine the engines speed.

, I twill be noticed that the relation of the chambered valve, 3,l tothe fixed piston member, V6, is substantially that of the two membersoi"A a dash-pot when considered with relation to theaction of the valveunder any force tending to open it, and the device does in fact act as adash-pot, in tending to' steady the action of the valve and prevent itfrom-fluttering or yielding too sensitively to rapid variations in thesuction, which may result from sudden changes of speed of the engine.

The construction shown in this application isa development from afundamental invention which is ,common to this, application and 'my'pending application No. 127,233, iled Octoberl 23, 1916; and

- this fundamental invention, common to both the applications, isclaimed in its broader phases in my said earlier application, and thebroad claims 'for that invention are not made in this application.

claim l. `In combination withfa suction passage constructed foraffording limited leakage.

past it Jfrom the lpiston chamber 'into the suction passage; a conduitleading from thel outer air into said piston chamber, and

means for controlling the air access to said v conduit.

2. In combination with a suction passage having an air inlet, a valvecontrolling said inlet opening inwardly; said valve having a pistonchamber opening inwardly; a head xed with respect vto the valve seatpositioned in the said piston chamber and acting piston-wise therein inthe .opening and closing movement of the valve, said head being,constructed for affording limited Aleakage j past it -from the pistonchamber intothe suction passage; a stem xedwith respect to the valveseat, aii'ording 4guidance for the valve and extending into saidchamber,

said stem having anair duct leading from the outer air into saidchamber, and means for controlling the air access to said air duct.

3. In combination with a suction passage having an air inlet, a valvecontrolling sald inlet and opening inwardly, said valve having a lpistonchamber opening inwardly;

a head fixed with respect to the valve seat,

positioned in said pistonl chamber and acting piston-wise therein in theopening and closing movement of the jvalve, said head being constructed'for aiording limited leakage past it from the lpiston chamber into thesuction passage; a conduit leading from the outer air into said pistonchamber; means for controlling the air access into said chamber, and aspring inthe chamber ive-acting between the valve and said head forresisting the opening movement of -the valve.

4. In combination with a suction passage having an air inlet,.a valvecontrolling said inlet and opening inwardly; a bridge across said inletand a stem extending .from said bridge for guidance of the valve in itsmovement toward and from'its seat; a head fixed with respect to thevalve Seat lpositioned in said piston chamber and acting piston-wisetherein in said opening and closing movement, said head beingconstructed forafording limited leakage past it from the piston chamiberinto the suction passage; said bridge and stem having ducts leading fromthe outer airinto the piston chamber of the valve; andeXteriorly-accessible means for controlling air access to said duct.

5. In combination with a suction passage having an air inlet; aspring-seated valve controlling said inlet and opening inwardly, saidvalve having a piston chamber 'opening inwardly; a head fixed withrespect to the valve seat, positioned in said piston chamber and actingpiston-wise therein in .the opening and closing movement lof thevalve,the head being constructed for affording limited leakage past it fromthe piston chamber into the suction passage; a conduit leading from theouter air into said piston chamber, and eXteriorly-accessible means forcontrolling the air access to said conduit.

In testimony whereof, I have hereunto set my hand at Detroit, Michigan,this 5th

